The present invention relates to a method of forming a micromachined structure, and in particular to a method of forming a micro-electro-mechanical system (MEMS) structure.
In recent years, micromachined devices, such as micro-mirror devices, microswitches, microactuators and the like, having small movable structures, have been gradually developed in many applications. Particularly, in the case of forming micromachined devices using technologies for semiconductor integrated circuits, such as those which include photolithographic processing, micromachined structures can be reproduced accurately. Thereby, the micromachined structures can be arrayed easily on a substrate, produced at low cost, and respond quicker than structures produced by prior techniques because of their reduced size.
Generally, movable micromachined structures can be actuated by electrostatic force, magnetic force or Van der Waals' force, etc., depending on choice of shapes and compositions. The micromachined structures can be realized by bulk micromachining or surface micromachining process using semiconductor IC manufacturing techniques of mass production at low cost and miniature size.
While micromachined structures are formed from a processing wafer or layer, the processing wafer or layer should be thin enough for the micromachined structures to respond quickly. However, it is noted that such thin processing wafers or layers are usually floppy and fragile.